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Blackwell Publishing IncMalden, USAJSMJournal of Sexual Medicine1743-6095© 2006 International Society for Sexual Medicine200633450454Original ArticleBreast Stimulation in Men and WomenLevin and Meston
450
Nipple/Breast Stimulation and Sexual Arousal in Young Men
and Women
Roy Levin, PhD,* and Cindy Meston, PhD†
*Department of Biomedical Science, University of Sheffield, Sheffield, UK; †Department of Psychology, University of Texas,
Austin, TX, USA
DOI: 10.1111/j.1743-6109.2006.00230.x
ABSTRACT
Introduction. The role of nipple/breast stimulation in influencing sexual arousal in men and women during
lovemaking has only been the subject of opinion-based comment rather than evidence-based study. No attempt to
question people about such sexual behavior has ever been undertaken.
Aim. The study was designed to ascertain the effects of nipple/breast manipulation in young men and women on
their sexual arousal.
Methods. A short questionnaire about nipple/breast stimulation during sexual activity was administered to 301 (148
men; 153 women) sexually experienced undergraduates (age range 17–29 years, 95% between 18 and 22).
Main Outcome Measures. Replies to questions in questionnaire.
Results. The major findings in regard to the women were that 81.5% reported that stimulation of their nipples/
breasts caused or enhanced their sexual arousal, 78.2% agreed that when sexually aroused such manipulation
increased their arousal, 59.1% had asked to have their nipples stimulated during lovemaking, and only 7.2% found
that the manipulation decreased their arousal. In regard to the men, 51.7% reported that nipple stimulation caused
or enhanced their sexual arousal, 39% agreed that when sexually aroused such manipulation increased their arousal,
only 17.1% had asked to have their nipples stimulated, and only 7.5% found that such stimulation decreased their
arousal.
Conclusion. Manipulation of the nipples/breasts causes or enhances sexual arousal in approximately 82% of young
women and 52% of young men with only 7–8% reporting that it decreased their arousal. Levin R, and Meston
C. Nipple/breast stimulation and sexual arousal in young men and women. J Sex Med 2006;3:450–454.
Key Words. Neurophysiological Studies of Sexual Function; Central Nervous System Control; Sexual Physiology;
Sexual Biochemistry
A brief report of the study (Levin RJ, Meston C.
Nipple stimulation and sexual arousal in young
men and women [abstract]. J Sex Med 2006;3(suppl
3):247.) was presented at the European Society of
Sexual Medicine meeting at Copenhagen, December 2005.
Introduction
N
ipple and breast stimulation is a frequent
characteristic of human sexual activity
especially employed by men [1] during the early
stages of lovemaking (so-called foreplay) to
induce in women sexual arousal. Kinsey et al.
[2] claimed, however, that “while this stimulates
the male erotically . . . the significance for the
J Sex Med 2006;3:450–454
female has probably been overestimated.” It was
also claimed that “relatively few females even
try to stimulate the breasts of their partners.”
These opinions were voiced over 50 years
ago and appear to be authority-based rather
than evidence-based. There is little or nothing
in the literature on the possible enhancement of
sexual arousal in women and especially in men
created by breast or nipple manipulation. It was
thus thought useful to establish by a brief questionnaire the present status of breast/nipple
stimulation among young men and women in
relation to the induction/enhancement of sexual
arousal.
© 2006 International Society for Sexual Medicine
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Breast Stimulation in Men and Women
Methods
Results
Participants
A total of 371 undergraduate students (180 men,
191 women) at the University of Texas at Austin
participated in this study in exchange for course
credit. Participants were enrolled in either the
2003–2004 Fall sessions (September–December)
or the 2004 Spring session ( January–May). Data
from participants who reported being sexually
inexperienced (defined as not having ever experienced sexual intercourse) were excluded from further analyses (N = 70). The final sample size was
148 men and 153 women. Participants varied in
age from 17 to 29 years (95% between 18 and 22),
and mean age was 19.23 years (SD = 1.5) and
18.78 years (SD = 1.2) for men and women,
respectively. The sample consisted of 56% Caucasian, 7% African American, 22% Hispanic, 14%
Asian American, <1% Native American, and 1%
“other ethnicity” participants. Ethnicity was
determined with the question, “What ethnicity do
you most identify with?”
One woman reported having had breast augmentation surgery. Data from her questionnaire were
excluded from further analyses as it is unclear to
what degree breast augmentation surgery may
affect nipple/breast sensitivity.
Regarding women, 81.5% reported that nipple/breast stimulation caused or enhanced their
sexual arousal, and that when they were sexually
aroused nipple/breast stimulation increased their
arousal. Only 7.2% reported that such stimulation caused a decrease in their arousal. Some
59.1% of the women have actively asked for the
stimulation from their partners, and some 37.7%
desired to have them stimulated but were not
able to ask for it to be undertaken (presumably
from shyness, or not wanting to appear too
demanding).
In the case of men, like women, nipple stimulation was excitatory for their sexual arousal but
the percentage was less than in women (51.7%
compared with 81.5%). Results from Likelihood
ratios indicated that this gender difference was
significant, L2 = 30.67, P < 0.001. Thirty-nine
percent of men (compared with 78.2% of women)
reported that nipple stimulation increased their
arousal when they were sexually aroused. This
gender difference was also significant (L2 = 46.27,
P < 0.001). Virtually, the same percentage of men
(7.5%) as women (7.2%) found that nipple stimulation decreased their arousal when sexually
aroused (L2 = 1.43, P = 0.49). A significantly
smaller percentage of men than women asked for
their nipples to be stimulated (17.1% vs. 59.1%,
L2 = 61.2, P < 0.001), and a significantly smaller
percentage would like to have the stimulation but
did not want to ask for it (19.8% vs. 37.7%,
L2 = 6.03, P < 0.05) (Table 1).
Procedures
Participants were administered a brief questionnaire consisting of questions inquiring about their
sexual arousal response to breast/nipple stimulation and a demographics questionnaire. Female
participants were also asked whether they had ever
received breast surgery. Participants responded
using a “Yes/No” response format.
The questionnaires were administered in small
groups of 5–10 same-sex individuals. To preserve
privacy, participants were given either partitions or
several feet of space from other participants. Participants were informed of the sexual nature of the
study before they applied to participate. Same-sex
researchers informed participants of the sexual
material, obtained consent, administered questionnaire packets, and answered participant questions
that arose during testing. Confidentiality was protected by assigning each participant with a randomized code number connected to all of his or her
data, and consent forms were kept in a separate file.
To help assure anonymity, upon completion, questionnaire packets were inserted into a large “drop
box” as participants exited the testing room. This
study was approved by the Human Subjects Ethics
committee at the University of Texas at Austin.
Statistical assessments of any significant differences (P > 0.05) among the data were undertaken
using Likelihood ratios, a test used to analyze categorical data [3].
Discussion
The majority of women surveyed (81.5%)
reported that stimulation of their nipples/breasts
caused or enhanced sexual arousal and increased
their arousal once they were already sexually
aroused. Although a comparatively lower proportion compared with women, the majority of men
(51.7%) also reported enhanced sexual arousal
with nipple stimulation and only a small proportion reported the activity decreased arousal. A significantly smaller percentage of men would like to
have had the stimulation during lovemaking but
did not want to ask for it. This gender difference
could feasibly be due to a number of factors
J Sex Med 2006;3:450–454
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452
Table 1
Levin and Meston
Response frequencies by gender (% Yes)
Item
Women
Men
1. Does stimulation of your nipples or breasts
cause or enhance sexual arousal?
2. When you are sexually aroused, does
stimulation of your nipples or breasts
increase your arousal?
3. When you are sexually aroused, does
stimulation of your nipples or breasts
decrease your arousal?
4. Have you ever asked to have your nipples or
breasts stimulated during lovemaking?
5. Would you like to have your nipples or
breasts stimulated during lovemaking but do
not want to ask for it to be done?*
81.5
51.7
78.2
39.0
7.2
7.5
59.1
17.1
37.7
19.8
N = 153 for women; N = 148 for men.
*Frequencies are calculated on those women (N = 61) and men (N = 24) who
answered “No” to question 4.
including gender differences in reporting biases or
social desirability, or gender roles ascribed to this
behavior. These results clearly do not support the
comments on nipple/breast stimulation by Kinsey
et al. [2] quoted in the Introduction section.
Exactly how nipple/breast stimulation influences sexual arousal is poorly understood. The
female nipple/areola is well innervated [4–6] and
when stimulated the nipple becomes erect and the
areola engorged [7]. The innervation of the male
nipple/areola, although similar to that of the
female nipple/areola [8], has been less well studied. It has been estimated that 50–60% of men also
show nipple erection on arousal [7]. The tactile
sensibility of the areola is regarded as protopathic
(primitive) as compared with epicritic (discriminatory) sensitivity of the skin [4]. In relation to tactile
stimuli, Robinson and Short [9] reported that after
puberty the sensitivity of all areas of the female
breast becomes significantly greater than that of
the male breast. While there have been a number
of brain imaging studies during sexual arousal in
men and women by visual sex stimulation indicating what areas become activated or inhibited [10–
14], as far as we know, there have been no similar
studies where just stimulating the breast or nipple
is the mode of arousal. We are thus ignorant of
how such stimulation activates sexual arousal in
the brain.
It has been proposed that prolactin specifically
released at orgasm by either coitus or masturbation inhibits sexual arousal in men and women
[15], although Levin [16] has pointed out that
women are known to be able to have multiple
serial orgasms. Although studies in men employing pharmacological methods of raising and lowJ Sex Med 2006;3:450–454
ering prolactin levels have shown that raised
prolactin inhibited subjective sexual arousal [17],
only some aspects of the arousal, such as the ejaculatory latency, were influenced by the induced
hyperprolactinemia with only small reductions in
sexual drive and functions. The new conclusion
was that although prolactin was important in the
postorgasmic regulation of sexual behavior, the
results did not “demonstrate a role for prolactin as
a simple and direct negative feedback mechanism.”
It is likely to be but “one signal within a network
of psycho-endocrine regulation of the sexual experience.” Sexual arousal in the brain occurs through
a complex interaction of multiple neurotransmitters (norepinephrine, acetylcholine, dopamine,
oxytocin, vasopressin, vasoactive intestinal peptide, and opioids) and sex steroids and is poorly
understood. Bancroft [18], reviewing the endocrinology of human sexual arousal, also commented
on its complexity and on the as yet uncertain
role(s) of the peptides prolactin and oxytocin. He
argued that the prolactin release at orgasm is an
“epiphenomenon of post-orgasmic inhibition of
dopamine activity, and not a hormonal mechanism
of functional importance.”
Experiments on the release of prolactin during
nipple/breast stimulation in nonlactating women
have given conflicting results. Kolodney et al. [19]
reported that it was increased in nine nonlactating
women either by self-stimulation or by manipulation from their husbands. Plasma prolactin levels
were not increased when men self-stimulated
themselves but when the stimulation was undertaken by their wives there was an immediate fourfold increase in the plasma prolactin levels of men.
Interestingly, no sexual arousal was reported by
any of the men during either self-stimulation or
stimulation by their wives. This difference suggested to Kolodney et al. [19] that psychological
concepts play a role in the release of prolactin in
men. A later study [20] in 11 nonpostpartum
women, however, did not show any increase in
prolactin during either solitary or multiple episodes of nipple stimulation over 24 hours.
Even in the case of breast-feeding when prolactin is definitely known to be released, there are
conflicting views on the effect on women’s sexuality. Newton [21] claimed that breast-feeding
women (who would be releasing prolactin at each
feed) were often interested in a quick return to
sexual intercourse but other authors suggest that
breast-feeding by new nursing women is a possible
cause of their low or absent libido [22]. Because of
these conflicting reports, it is not possible to come
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Breast Stimulation in Men and Women
to any conclusion about the action of prolactin
release during breast stimulation on human sexual
response. It is unfortunate but at our present level
of understanding little can be usefully said about
the nipple and central brain mechanisms of
arousal. There is a clear need for functional magnetic resonance imaging or positron-emission
tomography study on brain activity during nipple/
breast stimulation in both men and women.
Finally, a possible minor limitation of using a
“Yes/No” response format to the asked questions
(namely 1 and 2) is that some of the “No”
responses could reflect respondents indicating
“No” because they had never experienced the
behavior, rather than “No” because it was not
arousing. However, even if this postulate were so,
it should be stressed that this would necessarily
increase the proportion of our “Yes” responses,
rendering the data we report here a conservative
estimate of the enhancing effects of nipple stimulation on sexual arousal.
6
7
8
9
10
11
Conclusions
12
Manipulation of the nipple/breast during lovemaking causes or enhances sexual arousal for a
majority of both young women (81.5%) and men
(51.7%) and when experienced during sexual
arousal such manipulation further increased their
arousal. Only a very small minority of either sex
(approximately 7%) found that such manipulation
decreased their arousal.
13
14
Corresponding Author: Roy Levin, PhD, University
of Sheffield, Department of Biomedical Science,
Western Bank, Sheffield, S10 2TN, UK. Tel:
(0114) 2222320; Fax: (0114) 276541; E-mail: r.j.levin
@sheffield.ac.uk
15
Conflict of Interest: None.
16
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